1. Field of the Invention
The present invention relates to a vibration detection device optically detecting the displacement of a vibrating body.
2. Description of the Related Art
In recent years, recording systems and the like using a SACD (Super Audio Compact Disc) or 24-bit/96 kHz sampling have been used, and a trend toward higher sound quality is becoming mainstream. In such a trend, analog microphone apparatuses in related arts have a limit to record sound specifically with a high frequency of 20 kHz or over, so in the case where contents are recorded by making use of reproduction of high-frequency sound as a characteristic of the above-described recording systems, the analog microphone apparatuses are a bottleneck.
Moreover, the dynamic range of the analog microphone apparatuses does not reach 144 dB which is allowed in 24-bit recording as a characteristic of the above-described recording systems, so the analog microphone apparatuses do not sufficiently exploit a wide dynamic range.
Further, at a recording site, in analog microphone apparatuses in related arts, noises are increased due to a long analog cable run length, or it is necessary to supply phantom power from a mixing console to a condenser microphone, so it causes an impediment to total digitization in a recording/producing system.
Therefore, in recent years, some digital microphone apparatuses have been proposed (for example, refer to Japanese Unexamined Patent Application Publication Nos. H10-308998 and H11-178099).